Pulverizing mill



G. H. FRASER Apr. 10, 1923.

P'ULVERIZING MILL Original Filed Mar. '17, 1917 2 sheets-sheet? Patented Apr. 10, lQZS.

GEORGE HOLT FRASER, OF BROOKLYN, NEW YORK.

PULVERIZING MILL.

Application filed March 17 1917, Serial No. 155,390. Renewed December 15, 1922,

T 0 all whom it may concern:

Be it knownthat I, GEORGE HOLT FRAsER, a citizen of the United States, residing at No. 226 Quincy Street, in the borough of Brooklyn, county of Kings, city and State of New York, United States of America, manufacturer, have invented certain new and useful Improvements in Pulverizing Mills, of which the following is a specification.

This invention relates to machines for crushing, grinding or pulverizing, and particularly to such machineshaving a revolving ring and internal crushing rolls which crush the material against the inner face of the ring.

In such machines the rolls are movably mounted and are pressed outwardly to resist a crushing pressure from the inner face of the ring, and the ring or one of the rolls is driven positively, the other crushing parts being revolved from the driven part by traction. If the ring is the driving part it may be mounted on a fixed axis and if one of the rolls is the driving part it may yieldingly support the ring loosely.

My present invention aims to provide improvements applicable to either of these types of pulverizers, and especially applicable to the loose ring type.

To this end my present invention provides various improved features and combinations which, in their preferred form as applied to a loose ring pulverizer, will be hereinafter more fully set forth with reference to the accompanying drawings, in which,

Fig. 1 is a front elevation of a loose ring pulverizer provided with the preferred form of my improvements, partly in vertical section on the planes of the lines 11 in Fig. 4-

Fig. 2 is a. plan view'of the feed hopper thereof;

Fig. 3 is a fragmentary horizontal sec tion on the line 3 of Fig. 4; I

Fig. 4 is a side elevation, partly in sec tion cut on the planes of the lines l--- i of Fig. 1;

Fig. 5 is an enlarged fragmentary side view partly broken away to show the feed chute, and in section on the planes of the lines 5-5 of Fig. 6, and v Fig. 6 is an enlarged fragmentary front elevation partly broken away to showa section approximately on the planes of the lines 66 of Fig. 5. I

Referring to the drawings A is the top casing, B isthe bottom. casing, C are the covers, D is the top bearing, EE are the lower bearings, F are the feed spouts, G is the feed hopper, His the discharge outlet, at are the crushing rolls, 7) is the crushing ring, 0 are the roll shafts, d are the pressure springs, and e are the pressure screws of a pulverizer. l

These parts may be of any suitable construction for a ring and roller pulverizer, those shown comprising a frame or casing composed of the separably connected top and bottom and the removable side covers, which afford an internal crushing chamber in which the ring?) revolves loosely on the rolls a, being generally supported by the top roll which isdriven by a pulley,g on its shaft and which drives the ringand the other rolls by traction. The inner face of the ring is-concave and the peripheries of the rolls are convex, and the material being crushed falls through the legs of the hopper G and descends through the spouts F on each side of the ring and flows on to its inner face where it is held by centrifugal force and carried successively past the rolls which crush it until it is fine enough to discharge over the sides of the ring and descend into the chamber f to the outlet H. Pressure of the springs d is adjusted by the screws 6 until it is sufficient to overcome the crushing force of the material on the ring, and these springs yield to prevent breakage, and their respective bearings. move to equalize the crushing pressure between the rolls.v Automatic looks it hold the screwse when adjusted, a shut off gate 1' is provided for starting. and stopping the feed, and an adjustinggate is used to regulate the feed. The casing has side apertures is through which the ring passes, and shaft-slots Z for permitting radial movement of. the roll shafts.

According to the preferred form of my invention shown I provide a two duct feed hopper I in advance of-the feed gate, a

feed divider J in advance of the spouts, an

adjustable chute K within the ring, movable or adjustable cheek pieces L at the sides of the ring, roll apertures M inthe covers C, additional covers N therefor, rocking dust guards O for the shaft slotssliding on the covers N, double sliding spring pressed dust washers P sliding on the dustguards, movable collars Q supporting these washers, and lower bearings E having rigid upper arms suspended directly on and swinging positively from fixed pivotal axes above and near the center of gravity of these members so that these can be easily swung out of the wayof the ring to remove the'latterl 'Pulverizers of this character discharge coarse and fine material and a sieve is used to separate the fine from the coarse and return the coarse to the pulverizer with fresh feed and it is desirable that this returning coarse mate-rial should be pulverized fast as it i returned so that fresh feedshall only be admitted after this coarse material is all pulverized.

My invention provides the multiple condu it hopper I which is preferably mounted movably removably or reversibly on the hopper G, and which has a vertical conduit R havinga' top inlet S and a bottom outlet T fittinginto the mouth or regulatingchamber U of'the hopper G; which receives the coarse material returned from the sieve and delivers it iii a vertical column or path to the chamber U of the hopper, and which has one or more side inlets V and a fresh feed chamber or conduit communicating therewith sothat fresh feed must enter laterally against the descending column of returned material, the weight of which will automatically prevent inflow or fresh feed when the conduit R is fiill of returned-material, tius' insuring that returned material shall be ground in precedence to fresh feed material so long as there is'sufficient returned materialto prevent ingress of fresh terial. andthat fresh material ingress shall be controlled by the presence of the returned material. As shown the hopper I may be turned to anyof four positions to dispose thefresh feed chamber W where convenient, and the hopper I fits removably in thehopper G for thiswpur'po se instead of being formed integrally therewith.

Preferably I provide with or following the hopper I and between the regulating gate j' and the feed spouts a movable or adjustable divider J for dividing the descending feed and apportioning it between the two sides' of the ring so that it can flow on to the inner face of the ring at each side in suitable proportions to hold the ring in position axially or to compensate for its unequalwear' so that it will run truecentrally of the chamber 7". Any means movable transversely of the adjustinggate may be used but" I prefer to hinge the vertical damper'J on the apex of the bifurcated legs ofthe hopper (its that its upperedq'e can b? wung? under the gate to cut the stream "Later l as desired or eaeh'de "rid to handle m engaging the teeth of a rack n and held therein by a spring; 0; Preferably a shelf 39 is provided above'the damper. By properly regulating the damper undue axial stress of the ring or rolls may be obviated and these parts can be approximately maintained in true positions. I preferably provide for adjusting the delivery of material on the inner face of the ring by the movable or adjustable chute K, which preferably slides axially of the ring on feet 9 held oh supports 1*, and has wide sides a projecting in pockets t in the spouts F to receive material descending through the latter. The chute has a high back u and a contracted central mouth 1] which discharges the material centrally or at either side on the ring according to'the adjustment of the chute. Preferably the chute is automatically adjusted from the ring, as by levers w suspended from pivots m and having upper ends y struck by the ring when it moves eitcessively to one side and lower ends a carryingthe chute and removing it reversely of the movement of the ring to cause the chute to feed material to one side or the other of the center of the ring in opposition toits axial movement for the purpose of resisting or correcting this. I

Preferably I also provide movable adjustable or passive cheek pieces L at each side of the ring for limiting flow of material therefrom and preventingits contact with'the casing. As shown the cheek pieces L each have a lug or projection X resting on'a ledge Y and are adjustaloly connected by a bolt Z so that they are passive relatively but can slide axially of the ring to adapt themselves to the position it assumes and can be adjusted to regulate fineness of discharge or take up wear. The bolt ZGX- tends from side to side ofthe die to connect the cheek pieces. and may be at either side of the die when the ring is a loose ring as shown, but cannot be'exterior of the die as shown unless the ring is loose. as the cheek pieces should have an inside diameter not greater than that of the ring;

The covers C preferably each have a roll hole lil oppositc each roll. and large enough to pass the roll, and eacl'il'iole is preferably closed by an auxiliary cover bl having); a shaft slot Z. shown in Figxei which is closed by the rocking dust guard 01, shown in l fl and 4; which has a sen]i-cylindrical pro jection mountedslidingly in the bored out inner end of the adjacent bearing. as best seen in the lower left hand side of Fig. '1, to carry the weight of the dust guard from the bearing and cause it to swing with the bearing while it held against the cover N to close its shaft slot. Each dust guard has a clearance hole around the sha1't,,and between each bearing. 1ddust guardare use sliding. washers P held apart by springs Ito and supported on a revolving collar Q slidingly mounted and feathered on the shaft to prevent leakage of dust along the shaft or of oil from the hearing. The shaft sustains the sliding washers which work' in slideways or sockets in the rocking dust guards so that they cannot revolve but are free to slide and prevent leakage as the shaft wears into the bearing metal bushing.

The dust guard O has a projection or shoulder surrounding its convex or semispherical projection which is opposite and adjacent to the cylindrically bored inner lip or end of the adjacent bearing E, as shown in Fig. 1, against which this lip abuts it the bearing moves inwardly, so that these parts constitut reciprocal stop provisions for limiting movement of the bearing axially through the medium of the dust guard itself; but I prefer to utilize these only as emergency stop provisions and also provide additional provisions preferably proportioned to normally space the bearings slightly away from the dust guard so that the latter will not have to carry the axial stress of the bearing while sliding on the stationary cover N, and these additional stop provisions are preferably spaced beyond the edge of the sliding dust guard and opposite the stationary cover so that their movement and stress is independent of the dust guard and sustained by the stationary cover opposite the roll aperture which it closes. These additional means may be any suitable reciprocal provisions for movably guiding the hearing from the stationary cover, as for example the stop roller shown on the bearing E, Fig. 1, which rides on the stationary cover outwardly of the side edge of the dust guard as shown in Fig. 4 so that 1 it will roll on the stationary cover opposite the roll aperture closed by the latter, and thus sustain the bearing axially and normally prevent it ,from pressing the dust guard too tightly against the cover, so that the dust guard can normally slide under the pressure of its springs only, but should the rollers wear or be removed the dust guard itself will resist inwardly axial displacement of the bearing.

In operation the ringv revolves so that its side beneath the feed hopper descends and coarse material descends vertically through the conduit R and fresh material enters laterally when possible. Speed of feed is adjusted by thegate j, material is divided between the opposite sides of the ring by the divider J and is distributed on the ring by the chute K. The cheek pieces prevent the material from spilling off the ring, and it is carried around with the ring and successively crushed by the rolls until fine enough to flow between thesides of the ring and the cheek pieces. 7 Any roll is removableby swinging back its bearing, removing its "roll plate and said bearing.

'form, since it can be employed in whole or in part according to such modifications and. with such types of pulverizers as circum-- stances or the judgment of those skilled in the art may-dictate without departing from the spirit of the invention.

What is claimed'is:

1. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, and a revolving collar on said axle between said dust guard 2. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a cover for said aperture surrounding the axle,-a dust guard on said axle adjacent the said cover, and a sliding rotating collar slidingly mounted on said axle between said dust guard'and said bearng. I

3. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, and a collar splined to said axle between said dust guard and said bearing.

In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a

roll axle in said aperture having a bearingsurrounding the axle, a dust guard on said axle adjacent the said cover, a non-rotative washer on said axle between said dust guard and said axle bearing, and a sliding rotating collar slidingly mounted on said axle be tween said bearing and said washer and slidingly engaging said washer. I

6. In a mill of the type described, a grinding roll and a die, in combination with a. casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a COVBIIOI said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, a non-rotative washer on said axle between said dust guard and said axle bearing, and a collar splined on said axle between said bearing and said washer and bearing against said washer.

7. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, a pair of nonrotative washers on said axle between said. dust guard and said axle bearing, and a rotating collar mounted on said axle between said washers.

8. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the casing, a cover for said aperture surrounding the axle. a dust guard on said axle adjacent the said cover, a pair of-nonrotative washers on said axle between said dust guard and said axle bearing, and a rotating slidingcollar slidingly mounted on said axle between and bearing against said washers. I

9. In a mill of the type describecha ing roll and a die, in combination with a casing for the same having a side-aperture, a roll axle in said aperture having a bearing without the casing, a cover tor saidi ture surrounding the axle, a dust guard on said axle adjacent the said cover. a pair of non-rotative washers on said axle between said dust guard and said axle bearing, and a collar splined on said axle between and bearing against said washers.

10. In a. mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture'having bearing without the casing. a cover for said aperture surrouiuiling; the/axlew a dust guard on said axle adjacentthe said cover, a pair of non-rotative washers on said axle between said dust guard and said axle bearing, and a collar splined on said axle between and bearing against said washers, the outer one of said washers bearing against said axle bearing;

11. In a mill oi the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing. without the casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacentthe said cover, a pair of non-rotative washers on said axle between said dust guard and said axle bearing, axially yielding means between and pressing said washers away from one another, and a. collar mounted on saidaxle be- .tween said washers.

12'. In a mill of the type described, a grinding roll and a die, in combination with a casing for the same having a side aperture, a roll axle in said aperture having a bearing without the'casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, a pair of non-rotative washers on said axle between said dust guard and said axle hearing, axially yielding means between and pressing said washers away from one another, and a sliding collar slidingly mounted onsaid axle between and bearing against said washers.

13. In a mill of the type describecha grinding roll and a die, in combination'with a casing for the same having a side aper-,

ture, a roll axle in said aperture havinga bearing without the casing, a cover for said aperture surrounding the axle, a dust guard on said axle adjacent the said cover, a pair of non-rotative washers on said axle lee-,

tween said dust guard and said axle hearing, axially acting spaced springs between and pressing saidwashersaway from one another, and a collar splined on. said axle between and sustaining. said washers.

14;. In combination, an annular axially movable die revolving in an approximately vertical plane and having an internal crushing face, a movable and rotatable crushing roll within and eccentric of said die and having'a peripheral crushingface reciprocal to the in-nerface of said. die, means for revolving one of said parts, means for supplying material to be crushed to said parts, and means within and movable axially of said die for adjustingthe position axially of said dieat which such material is delivered on to the inner face of said die for varying the position of said die axially.

15; In combination, an annular axially movable die'revolving in an approximately vertical plane and having an internal crushing face, a movable and rota-table crushing roll within and eccentric of said die and having a peripheral crushing face reciprocal to the inner face of said die, means for revolving one of said parts, means for supplying material to be crushed to said parts, means for delivering. suchmaterial on to the inner face 0f such die from .both sides. of

the latter, means for varying the quantity signed my name in the presence of two subof such material supplied to such die, and scribing Witnesses.

means for apportioning the quantity of such material delivered at the respective GEORGE O R 1 v 5 sides of said die for varying the position of vsaid die axially.

In witness whereof, I have hereunto \Vitnesses ANTONIO BUoNo, JOSEPH P. TIGHE. 

